Estrogenic compounds as anti-mitotic agents

ABSTRACT

The application discloses methods of treating mammalian diseases characterized by abnormal cell mitosis by administering estradiol derivatives including those comprising colchicine or combretastatin A-4 structural motifs of the general formulae found below in a dosage sufficient to inhibit cell mitosis. The application discloses novel compounds used in the methods.

BACKGROUND OF THE INVENTION

[0001] This invention relates to treating disease states characterizedby abnormal cell mitosis.

[0002] Cell mitosis is a multi-step process that includes cell divisionand replication (Alberts, B. et al. In The Cell, pp. 652-661 (1989);Stryer, E. Biochemistry (1988)). Mitosis is characterized by theintracellular movement and segregation of organelles, including mitoticspindles and chromosomes. Organelle movement and segregation arefacilitated by the polymerization of the cell protein tubulin.Microtubules are formed from α and β tubulin polymerization and thehydrolysis of GTP. Microtubule formation is important for cell mitosis,cell locomotion, and the movement of highly specialized cell structuressuch as cilia and flagella.

[0003] Microtubules are extremely labile structures that are sensitiveto a variety of chemically unrelated anti-mitotic drugs. For example,colchicine and nocadazole are anti-mitotic drugs that bind tubulin andinhibit tubulin polymerization (Stryer, E. Biochemistry (1988)). Whenused alone or in combination with other therapeutic drugs, colchicinemay be used to treat cancer (WO-9303729-A, published Mar. 4, 1993;J03240726-A, published Oct. 28, 1991), alter neuromuscular function,change blood pressure, increase sensitivity to compounds affectingsympathetic neuron function, depress respiration, and relieve gout(Physician's Desk Reference, Vol. 47, p. 1487, (1993)).

[0004] Estradiol and estradiol metabolites such as 2-methoxyestradiolhave been reported to inhibit cell division (Seegers, J. C. et al. J.Steroid Biochem. 32, 797-809 (1989); Lottering, M-L. et al. Cancer Res.52, 5926-5923 (1992); Spicer, L. J. and Hammond, J. M. Rol. and Cell.Endo. 64, 119-126 (1989); Rao, P. N. and Engelberg, J. Exp. Cell Res.48, 71-81 (1967)). However, the activity is variable and depends on anumber of in vitro conditions. For example, estradiol inhibits celldivision and tubulin polymerization in some in vitro settings (Spicer,L. J. and Hammond, J. M. Mol. and Cell. Endo. 64,-119-126 (1989);Ravindra, R., J. Indian Sci. 64(c) (1983)), but not in others(Lottering, M-L. et al. Cancer Res. 52, 5926-5923 (1992); Ravindra, R.,J. Indian Sci. 64(c) (1983)). Estradiol metabolites such as2-methoxyestradiol will inhibit cell division in selected in vitrosettings depending on whether the cell culture additive phenol red ispresent and to what extent cells have been exposed to estrogen.(Seegers, J. C. et al. Joint NCI-IST Symposium. Biology and Therapy ofBreast Cancer. 9/25-9/27, 1989, Genoa, Italy, Abstract A58).

[0005] Numerous diseases are characterized by abnormal cell mitosis. Forexample, uncontrolled cell mitosis is a hallmark of cancer. In addition,cell mitosis is important for the normal development of the embryo,formation of the corpus luteum, wound healing, inflammatory and immuneresponses, angiogenesis and angiogenesis related diseases.

SUMMARY OF THE INVENTION

[0006] I have discovered that certain compounds within the scope of thegeneral formulae set forth below in the claims are useful for treatingmammalian diseases characterized by undesired cell mitosis. Withoutwishing to bind myself to any particular theory, such compoundsgenerally inhibit microtuble formation and tubulin polymerization and/ordepolymerization. Compounds within the general formulae having saidinhibiting-activity are preferred. Preferred compositions may alsoexhibit a change (increase or decrease) in estrogen receptor binding,improved absorbtion, transport (e.g. through blood-brain barrier andcellular membranes), biological stability, or decreased toxicity. I havealso discovered certain compounds useful in the method, as described bythe general formulae of the claims.

[0007] A mammalian disease characterized by undesirable cell mitosis, asdefined herein, includes but is not limited to excessive or abnormalstimulation of endothelial cells (e.g., atherosclerosis), solid tumorsand tumor metastasis, benign tumors, for example, hemangiomas, acousticneuromas, neurofibromas, trachomas, and pyogenic granulomas, vascularmalfunctions, abnormal wound healing, inflammatory and immune disorders,Bechet's disease, gout or gouty arthritis, abnormal angiogenesisaccompanying: rheumatoid arthritis, psoriasis, diabetic retinopathy, andother ocular angiogenic diseases such as retinopathy of prematurity(retrolental fibroplasic), macular degeneration, corneal graftrejection, neovascular glaucoma and Osler Weber syndrome. Otherundesired angiogenesis involves normal processes including ovulation andimplantation of a blastula. Accordingly, the compositions describedabove can be used to block ovulation and implantation of a blastula orto block menstruation (induce amenorrhea).

[0008] The bond indicated by C...C is absent or, in combination with theC---C bond is the unit HC═CH.

[0009] Other features and advantages of the invention will be apparentfrom the following description of preferred embodiments thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The drawings are first described.

[0011]FIG. 1 is a graph illustrating the inhibition of tubulinpolymerization by 2-methoxyestradiol described by Example 1 below.

[0012]FIG. 2 is a graph illustrating the inhibition of colchicinebinding to tubulin by 2-methoxyestradiol described by Example 2 below.

[0013]FIG. 3 depicts: I. colchicine, 2-methoxyestradiol andcombretastatin A-4, and II. various estradiol derivatives comprisingcolchicine (a-c) or combretastatin A-4 (d) structural motifs asdescribed below.

COMPOUNDS ACCORDING TO THE INVENTION

[0014] As described below, compounds that are useful in accordance withthe invention include novel estradiol derivatives that bind tubulin,inhibit microtubule formation or exhibit anti-mitotic properties.Specific compounds according to the invention are described below. Thoseskilled in the art will appreciate that the invention extends to othercompounds within the formulae given in the claims below, having thedescribed characteristics. These characteristics can be determined foreach test compound using the assays detailed below and elsewhere in theliterature.

[0015] Without wishing to bind myself to specific mechanisms or theory,it appears that certain compounds that are known to inhibit microtubuleformation, bind tubulin and exhibit anti-mitotic properties such ascolchicine and combretastatin A-4 share certain structural similaritieswith estradiol. FIG. 3 illustrates the molecular formulae of estradiol,colchicine, combretastatin A-4, and improved estradiol derivatives thatbind tubulin inhibit microtubule assembly and exhibit anti-mitoticproperties. Molecular formulae are drawn and oriented to emphasizestructural similarities between the ring structures of colchicine,combretastatin A-4, estradiol, and certain estradiol derivatives.Estradiol derivatives are made by incorporating colchicine orcombretastatin A-4 structural motifs into the steroidal backbone ofestradiol.

[0016]FIG. 3, part I, depicts the chemical formulae of colchicine,2-methoxyestradiol and combretastatin A-4. FIG. 3, part IIa-d,illustrates estradiol derivatives that comprise structural motifs foundin colchicine or combretastatin A-4. For example, part II a-c showsestradiol derivatives with an A and/or B ring expanded from six to sevencarbons as found in colchicine and part IId depicts an estradiolderivative with a partial B ring as found in combretastatin A-4. Each Cring of an estradiol derivative, including those shown in FIG. 3, may befully saturated as found in 2-methoxyestradiol. R₁₋₆ represent a subsetof the substitution groups found in the claims. Each R₁→R₆ canindependently be defined as —R₁, OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I,or —C═CH.

[0017] Anti-mitotic Activity In Situ

[0018] Anti-mitotic activity is evaluated in situ by testing the abilityof an improved estradiol derivative to inhibit the proliferation of newblood vessel cells (angiogenesis). A suitable assay is the chick embryochorioallantoic membrane (CAM) assay described by Crum et al. Science230:1375 (1985). See also, U.S. Pat. No. 5,001,116, hereby incorporatedby reference, which describes the CAM assay. Briefly, fertilized chickembryos are removed from their shell on day 3 or 4, and amethylcellulose disc containing the drug is implanted on thechorioallantoic membrane. The embryos are examined 48 hours later and,if a clear avascular zone appears around the methylcellulose disc, thediameter of that zone is measured. Using this assay, a 100 mg disk ofthe estradiol derivative 2-methoxyestradiol was found to inhibit cellmitosis and the growth of new blood vessels after 48 hours. This resultindicates that the anti-mitotic action of 2-methoxyestradiol can inhibitcell mitosis and angiogenesis.

[0019] Anti-Mitotic Activity In Vitro

[0020] Anti-mitotic activity can be evaluated by testing the ability ofan estradiol derivative to inhibit tubulin polymerization andmicrotubule assembly in vitro.

[0021] Microtubule assembly is followed in a Gilford recordingspectrophotometer (model 250 or 2400S) equipped with electronictemperature controllers. A reaction mixture (all concentrations refer toa final reaction volume of 0.25 μl) contains 1.0M monosodium glutamate(ph 6.6), 1.0 mg/ml (10 μM) tubulin, 1.0 M Mgcl₂, 4% (v/v)dimethylsulfoxide and 20-75 μM of a composition to be tested. The 0.24ml reaction mixtures are incubated for 15 miii. at 37° C. and thenchilled on ice. After addition of 10 μl 2.5 mM GTP, the reaction mixtureis transferred to a cuvette at 0°C., and a baseline established. At timezero, the temperature controller of the spectrophotometer is set at 37°C. Microtubule assembly is evaluated by increased turbity at 350 nm.Alternatively, inhibition of microtubule assembly can be followed bytransmission electron microscopy as described in Example 2 below.

[0022] Indications

[0023] The invention can be used to treat any disease characterized byabnormal cell mitosis. Such diseases include, but are not limited to:abnormal stimulation of endothelial cells (e.g., atherosclerosis), solidtumors and tumor metastasis, benign tumors, for example, hemangiomas,acoustic neuromas, neurofibromas, trachomas, and pyogenic granulomas,vascular malfunctions, abnormal wound healing, inflammatory and immunedisorders, Bechet's disease, gout or gouty arthritis, abnormalangiogenesis accompanying: rheumatoid arthritis, psoriasis, diabeticretinopathy, and other ocular angiogenic diseases such as retinopathy ofprematurity (retrolental fibroplasic), macular degeneration, cornealgraft rejection, neuroscular glacoma and Oster Webber syndrome.

[0024] Improved Estradiol Derivative Synthesis

[0025] Known compounds that are used in accordance with the inventionand precursors to novel compounds according to the invention can bepurchased, e.g., from Sigma Chemical Co., St. Louis, Steroloids andResearch Plus. Other compounds according to the invention can besynthesized according to known methods from publicly availableprecursors.

[0026] The chemical synthesis of estradiol has been described (Eder, V.et al., Ber 109, 2948 (1976); Oppolzer, D. A. and Roberts, D. A. Hely.Chim. Acta. 63, 1703, (1980)). Synthetic methods for makingseven-membered rings in multi-cyclic compounds are known (Nakamuru, T.et al. Chem. Pharm. Bull. 10, 281 (1962); Sunagawa, G. et al. Chem.Pharm. Bull. 9, 81 (1961); Van Tamelen, E. E. et al. Tetrahedran 14,8-34 (1961); Evans, D. E. et al. JACS 103, 5813 (1981)). Those skilledin the art will appreciate that the chemical synthesis of estradiol canbe modified to include 7-membered rings by making appropriate changes tothe starting materials, so that ring closure yields seven-memberedrings. Estradiol or estradiol derivatives can be modified to includeappropriate chemical side groups according to the invention by knownchemical methods (The Merck index, 11th Ed., Merck & Co., Inc., Rahway,N.J. USA (1989), pp. 583-584).

Administration

[0027] The compositions described above can be provided asphysiologically acceptable formulations using known techniques, andthese formulations can be administered by standard routes. In general,the combinations may be administered by the topical, oral, rectal orparenteral (e.g., intravenous, subcutaneous or intramuscular) route. Inaddition, the combinations may be incorporated into biodegradablepolymers allowing for sustained release, the polymers being implanted inthe vicinity of where delivery is desired, for example, at the site of atumor. The biodegradable polymers and their use are described in detailin Brem et al., J. Neurosurg. 74:441-446 (1991).

[0028] The dosage of the composition will depend on the condition beingtreated, the particular derivative used, and other clinical factors suchas weight and condition of the patient and the route of administrationof the compound. However, for oral administration to humans, a dosage of0.01 to 100 mg/kg/day, preferably 0.01-1 mg/kg/day, is generallysufficient.

[0029] The formulations include those suitable for oral, rectal, nasal,topical (including buccal and sublingual), vaginal or parenteral(including subcutaneous, intramuscular, intravenous, intradermal,intraocular, intratracheal, and epidural) administration. Theformulations may conveniently be presented in unit dosage form and maybe prepared by conventional pharmaceutical techniques. Such techniquesinclude the step of bringing into association the active ingredient andthe pharmaceutical carrier(s) or excipient(s). In general, theformulations are prepared by uniformly and intimately bringing intoassociate the active ingredient with liquid carriers or finely dividedsolid carriers or both, and then, if necessary, shaping the product.

[0030] Formulations of the present invention suitable for oraladministration may be presented as discrete units such as capsules,cachets or tablets each containing a predetermined amount of the activeingredient; as a powder or granules; as a solution or a suspension in anaqueous liquid or a non-aqueous liquid; or as an oil-in-water liquidemulsion or a water-in-oil emulsion and as a bolus, etc.

[0031] A tablet may be made by compression or molding, optionally withone or more accessory ingredients. compressed tablets may be prepared bycompressing, in a suitable machine, the active ingredient in afree-flowing form such as a powder or granules, optionally mixed with abinder, lubricant, inert diluent, preservative, surface-active ordispersing agent. Molded tables may be made by molding, in a suitablemachine, a mixture of the powdered compound moistened with an inertliquid diluent. The tablets may optionally coated or scored and may beformulated so as to provide a slow or controlled release of the activeingredient therein.

[0032] Formulations suitable for topical administration in the mouthinclude lozenges comprising the ingredients in a flavored basis, usuallysucrose and acacia or tragacanth; pastilles comprising the activeingredient in an inert basis such as gelatin and glycerin, or sucroseand acacia; and mouthwashes comprising the ingredient to be administeredin a suitable liquid carrier.

[0033] Formulations suitable for topical administration to the skin maybe presented as ointments, creams, gels and pastes comprising theingredient to be administered in a pharmaceutical acceptable carrier. Apreferred topical delivery system is a transdermal patch containing theingredient to be administered.

[0034] Formulations for rectal administration may be presented as asuppository with a suitable base comprising, for example, cocoa butteror a salicylate.

[0035] Formulations suitable for nasal administration, wherein thecarrier is a solid, include a coarse powder having a particle size, forexample, in the range of 20 to 500 microns which is administered in themanner in which snuff is taken, i.e., by rapid inhalation through thenasal passage from a container of the powder held close up to the nose.Suitable formulations, wherein the carrier is a liquid, foradministration, as for example, a nasal spray or as nasal drops, includeaqueous or oily solutions of the active ingredient.

[0036] Formulations suitable for vaginal administration may be presentedas pessaries, tampons, creams, gels, pastes, foams or spray formulationscontaining in addition to the active ingredient such as carriers as areknown in the art to be appropriate.

[0037] Formulations suitable for parenteral administration includeaqueous and non-aqueous sterile injection solutions which may containanti-oxidants, buffers, bacteriostats and solutes which render theformulation isotonic with the blood of the intended recipient; andaqueous and non-aqueous sterile suspensions which may include suspendingagents and thickening agents. The formulations may be presented inunit-dose or multi-dose containers, for example, sealed ampules andvials, and may be stored in a freeze-dried (lyophilized) conditionsrequiring only the addition of the sterile liquid carrier, for example,water for injections, immediately prior to use. Extemporaneous injectionsolutions and suspensions may be prepared from sterile powders, granulesand tables of the kind previously described.

[0038] Preferred unit dosage formulations are those containing a dailydose or unit, daily sub-dose, as herein above recited, or an appropriatefraction thereof, of the administered ingredient.

[0039] It should be understood that in addition to the ingredients,particularly mentioned above, the formulations of this invention mayinclude other agents convention in the art having regard to the type offormulation in question, for example, those suitable for oraladministration may include flavoring agents.

EXAMPLE 1

[0040]FIG. 1 illustrates the inhibition of tubulin polymerization by2-methoxyestradiol.

[0041] A. Each reaction mixture (all concentrations refer to the finalreaction volume of 0.25 ml) contained 1.0 M monosodium glutamate (pH6.6), 1.0 mg/ml (10 μM) tubulin, 1.0 mM MGCl₂, 4% (v/v)dimethylsulfoxide, and either o (curve 1), 20 μM (curve 2), 40 μM (curve3), or 75 μM (curve 4) 2-methoxyestradiol. The 0.24 ml reaction mixtureswere incubated for 15 min at 37° C. and chilled on ice. After additionof 10 μl of 2.5 mM GTP the reaction mixtures were transferred tocuvettes held at 0° C., and baselines were established. At time zero thetemperature controller was set at 37° C. At the times indicated by thevertical dashed lines the temperature controller was set at theindicated temperatures.

[0042] B. Each reaction mixture contained 0.8 M monosodium glutamate (pH6.6), 1.2 mg/ml (12 μM) tubulin, 4% (v/v) dimethylsulfoxide, and either0 (curve 1), 1.0 μM (curve 2), 2.0 μM (curve 3), 3.0 μM (curve 4), or4.0 μM (curve 5) 2-methoxyestradiol. The 0.24 ml reaction mixtures wereincubated for 15 min at 26° C. and chilled on ice. After addition of 10μl of 10 mM GTP the reaction mixtures were transferred to cuvettes heldat 0° C., and baselines were established. At time zero the temperaturecontroller was set at 26° C. At the time indicated by vertical dashedline the temperature controller was set at 0° C.

EXAMPLE 2

[0043] Transmission electron microscopy (TEM) can show differencesbetween the morphology of polymerized tubulin formed in the absence orpresence of 2-methoxyestradiol. After a 30 min incubation (37° C.) ofreaction mixtures containing the components described in Example 1, 75μM 2-methoxyestradiol was added, and aliquots were placed on 200-meshcarbon coated copper grids and stained with 0.5% (w/v) uranyl acetate.TEM magnifications from 23,100×to 115,400×were used to visualizedifferences in tubulin morphology.

EXAMPLE 3

[0044]FIG. 2 illustrates that 2-methoxyestradiol inhibits colchicinebinding to tubulin. Reaction conditions were as described in the text,with each reaction mixture containing 1.0 pM tubulin, 5% (v/v) dimethylsulfoxide, 5 pM [³H]colchicine, and inhibitor at the indicatedconcentrations. Incubation was for 10 min at 37° C. Symbols as follows:∘, 2-methoxyestradiol; , combretastatin A-4; Δ, dihydrocombretastatinA-4. Combretastatin A-4 and dihydrocombretastatin A-4 are compounds withanti-mitotic activity similar to colchicine.

EXAMPLE 4

[0045] Table 1 illustrates the inhibitory effects on tubulinpolymerization in vitro exhibited by estradiol or estradiol derivatives,plant anti-mitotic compounds such as colchicine, combretastatin A-4 orother plant compounds The method is given in Example 1.

EXAMPLE 5

[0046] Table 2 lists estrogens, estradiol or estradiol derivatives thatinhibit colchicine binding to tubulin, by the method given in Example 3.TABLE 1 IC₅₀ (μM ± S.D.) Estrogenic Compound 2-Methoxyestradiol  1.9 ±0.2 Diethylstilbestrol  2.4 ± 0.4 2-Bromoestradiol  4.5 ± 0.62-Methoxyestrone  8.8 ± 1 17-Ethynylestradiol 10.0 ± 2 2-Fluoroestradiol27.0 ± 6 Estradiol 30.0 ± 6 Estrone >402-Methoxy-17-ethynylestradiol >40 Estriol >40 2-Methoxyestriol >40Estradiol-3-O-methyl ether >40 2-Methoxyestradiol-3-O-methyl ether >404-Methoxyestradiol >40 4-Methoxyestradiol-3-O-methyl ether >40 PlantProducts Colchicine 0.80 ± 0.07 Podophyllotoxin 0.46 ± 0.02Combretastatin A-4 0.53 ± 0.05 Dihydrocombretastatin A-4 0.63 ± 0.03

[0047] IC₅₀ values are defined as the concentration of an estradiolderivative required to inhibit tubulin polymerization by 50%. IC₅₀values were obtained in at least two independent experiments fornon-inhibitory agents (IC₅₀>40 μM) and at least three independentexperiments for inhibitory compounds. IC₅₀ values were obtainedgraphically, and average values are presented. S.D., standard deviation.TABLE 2 Estrogenic Compound Percent inhibition ± S.D. 2-Methoxyestradiol82 ± 2 2-Methoxyestrone 57 ± 6 17-Ethynylestradiol 50 ± 7 Estradiol 38 ±4 Diethylstilbestrol 30 ± 4

[0048] Reaction conditions were described in Example 3, with eachreaction mixture containing 1.01M tubulin, 5% (v/v) dimethyl sulfoxide,2 μM [³H]colchicine, and 100 μM inhibitor. Incubation was for 10 min at37° C. Average values obtained in three independent experiments arepresented in the table, except for 2-methoxyestrone, which was onlyexamined twice. S.D., standard deviation.

What is claimed is:
 1. A method for treating a mammalian diseasecharacterized by abnormal cell mitosis, said method comprisingadministering to a mammal a cell-mitosis-inhibiting compound of theformula below, said compound being administered in an amount sufficientto inhibit cell mitosis:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(i), R_(j), R_(k), R_(l), R_(m), R_(o),independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; andR_(g) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NR₂, —Br, —I, or —C═CH; or B)each R_(a), R_(b), R_(c), R_(f), R_(k), R_(l), R_(o), independently is—R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and each R_(d), R_(e),R₁, R_(j), R_(m), independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F,—NHR₂, —Br or —I; and R_(g) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂,—Br, —I, or —C═CH; and II. Z′ is defined as follows: A) Z′ is X, where Xis >COR₁,

 or B) Z′ is

 where R_(n is —R) ₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; and X′ is X, asdefined above; or X′ is >C═O; and III. Z″ is defined as follows: A) Z″is Y, where Y is —O—,

 where n is 0-6; or B) Z″ is

 where R_(p) is —R₁, —OR, —SR₁, —F, —NHR₂, —Br or —I; and IV. providedthat when each R_(b), R_(c), R_(d), R_(e), R_(i), R_(j), R_(k), R_(l),R_(m) and R_(o) is H; R_(f) is —CH₃; R_(g) is —OH; Z′ is >COH; and Z″ is>CH₂; then R_(a) is not —H; where, in each formula set forth above, eachR₁ and R₂ independently is —H, or substituted or unsubstituted alkyl,alkenyl or alkynl group of 1-6 carbons.
 2. A method for treating amammalian disease characterized by abnormal cell mitosis, said methodcomprising administering to a mammal a cell-mitosis-inhibiting compoundof the formula below, said compound being administered in an amountsufficient to inhibit cell mitosis:

wherein: I. R_(a)-R_(k) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(g), R_(h), R_(i), R_(k) independently is —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and R₀ is —R₁, —OR₁, —OCOR₁, —SR₁,—F, —NHR₂, —Br, —I or —C═CH; or B) each R_(a), R_(b), R_(c), R_(d),R_(k), independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I;and each R_(eg), R_(h), R_(i), independently is ═O, —R₁, —OR₁, —OCOR₁,—SR₁, —F. —Br, or —I; and R_(e) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —Br,—I or —C═CH; and II. Z′ is defined as follows: A) Z′ is X, where X is>COR₁,

 or B) Z′ is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I, and X′ is X, asdefined above; or X′ is also >C═O; and III. Z″ is defined as follows: A)Z″ is Y, where Y is —O—,

 >CHR₁,

 where n is 0-6; or B) Z″ is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and R₂ independently is —H, orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 3. A method for treating a mammalian disease characterized byabnormal cell mitosis, said method comprising administering to a mammala cell-mitosis-inhibiting compound of the formula below, said compoundbeing administered in an amount sufficient to inhibit cell mitosis:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(j), R_(f), R_(k), R_(l), R_(o)independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, NHR₂, —Br, or —I; andR_(g) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or —C═CH; or B)each R_(a), R_(b), R_(c), R_(f), R_(k), R_(i), independently is —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and each R_(d), R_(e), R_(i),R_(j), R_(m), R_(o) independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F,—NHR₂, —Br, or —I; and R_(g) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂,—Br, —I or —C═CH; II. Z is defined as follows: A) Z is Y, where Y is—O—,

 where n is 0-6; or B) Z is

 where R_(n) is —R₁, —OR₁, —SR₁₁—F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and R₂ independently is —H, orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 4. A method for treating a mammalian disease characterized byabnormal cell mitosis, said method comprising administering to a mammala cell-mitosis-inhibiting compound of the formula below, said compoundbeing administered in an amount sufficient to inhibit cell mitosis:

wherein: I. R_(a)-R_(k) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(g), R_(h), independently is —R₁, —OR₁, —OCOR₁, —SR₁,—F, —NHR₁, —Br, or —I; and R_(e) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁,—Br, —I or —C═CH; or B) each R_(a), R_(b), R_(c), R_(d), independentlyis —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, or —I and each R_(g), R_(h),R_(i), R_(k) independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁,—Br or —I; and R_(e) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁₁—F, —NHR₁, —Br, —Ior —C═CH; and II. Z is defined as follows: A) Z is Y, where Y is —O—,

 where n is 0-6; or B) Z is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and 2 independently is —H, orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 5. A method for treating a mammalian disease characterized byabnormal cell mitosis, said method comprising administering to a mammala cell-mitosis-inhibiting compound of the formula below, said compoundbeing administered in an amount sufficient to inhibit cell mitosis:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(g), R_(h), R_(j), R_(k), R_(l), R_(m),R_(n), R_(o) independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br,or —I; and R_(i) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or—C═CH; or B) each R_(a), R_(d), R_(f), R_(j), R_(m), R_(n), R_(o)independently is —R₁, —OR₁, —OCR₁, —SR₁, —F, —NHR₂, —Br, or —I; and eachR_(b), R_(c) R_(d), R_(g), R_(h), R_(k), R, independently is ═O, —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R_(i) is ═O, —R₁, —OR₁,—OCOR₁, —SR₁, —F, —Br, —I or —C≡CH; or C) each R_(a), R_(b), R_(c),R_(d), R_(f), R_(j), R_(m), R_(n), R_(o) independently is —R₁, —OR₁,—OCR₁, —SR₁, —F, —NHR₂, —Br, —I and each R_(e), R_(g), R_(h), R_(k),R_(l) independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or—I; and R₁ is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —Br, —I or —C═CH; II. Zis defined as follows: A) Z is X, where X is >COR₁,

 or B) Z is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; and X′ is X, asdefined above; or X′ is >C═O; where, in each formula set forth above,each R₁ and R₂ independently is —H, or substituted or unsubstitutedalkyl, alkenyl or alkynl group of 1-6 carbons; and the bond indicated byC...C is absent or, in combination with the C—C bond, is the unit HO═CH.6. A method for treating a mammalian disease characterized by abnormalcell mitosis, said method comprising administering to a mammal acell-mitosis-inhibiting compound of the formula below, said compoundbeing administered in an amount sufficient to inhibit cell mitosis:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(e), R_(g), R_(h), R_(k), R_(l), R_(n), R_(o) independently is—R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and R₁ is —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or —C═CH; or B) each R_(a), R_(e),R_(l), R_(m), R_(n), R_(o) independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F,—NHR₂, —Br, —I and each R_(b), R_(c), R_(g), R_(h) is ═O, —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R₁ is ═O, —R₁, —OR₁, —OCOR₁,—SR₁, —F, —NHR₁, —Br, —I or —C═CH; or C) each R_(a), R_(b), R_(c),R_(e), R_(k), R_(m), R_(n), R_(o) independently is —R₁, —OR₁, —OCOR₁,—SR₁, —F, —NHR₂, —Br, —I, and each R_(h), R_(i) independently is ═O,—R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R_(i) is ═0, —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, —I or —C═CH; and I. Z is defined asfollows: A) z is X, where X is >COR₁,

 or B) Z is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I, and X′ is X, asdefined above; or X′ is ═O; where, in each formula set forth above; eachR₁ and R₂ independently is —H, or substituted or unsubstituted alkyl,alkenyl or alkynl group of 1-6 carbons; and the bond indicated by COLICis absent or, in combination with the C...C bond is the unit HC═CH.
 7. Acompound of the general formula below, said compound being acell-mitosis-inhibiting compound:

wherein: I. R_(a)-R_(o) are defined as follows: (A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(i), R_(j), R_(k), R_(l), R_(m), R_(o),independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; andR_(g) is —R₁, —OR₁, —OCOR₁, —SR₁, —F. —NHR₂, —Br, —I or —C═CH; or (B)each R_(a), R_(b), R_(c), R_(f), R_(k), R_(l), R_(o), is —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and each R_(d), R_(e), R₁, R_(j),R_(m), independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br or—I; and R_(g) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or—C═CH; and II. Z′ is defined as follows: A) Z′ is X, where X is >COR₁,

 or B) Z′ is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; or X′ is X, asdefined above; or X′ is >C═O; and III. Z″ is defined as follows: A) Z′is Y, where Y is —O—,

 where n is 0-6; or B) Z″ is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, NHR₂, —Br or —I; provided thatwhen: 3) each R_(b), R_(c), R_(d), R_(e), R_(j), R_(k), R_(l), R_(m), is—H; R_(f) is —CH₃; R_(g) is —OH,

 R_(i) is —H, —OH, or ═O; R_(o) is —H or —Br; Z′ is >COH; and Z″ is >CH₂or —OH; then R_(a) is not —F, —Br, —OH or —H; and 4) each R_(b), R_(c),R_(d), R_(e), R_(i), R_(j), R_(k), R_(l), R_(m), is —H; R_(f) is —CH₃;R_(g) is —OH; and Z″ is >CH₂; then Z′ is not >COCH₃ or

 and each R_(a), R_(o) independently or together are not —OCH₃ or —H;and 5) each R_(c), R_(e), R_(j), R_(k), R_(l), R_(m), R_(o) is —H; R_(a)is —H or —OCH₃; R_(b) is —H or —CH₃; R_(d) is —OH; R_(f) is —CH₃; is ═O;R_(i) is —OH, ═or —C═CH; and Z″ is >CH₂; then Z′ is not >COH;

 or —H; where, in each formula set forth above, each R₁ and R₂independently is —H, or substituted or unsubstituted alkyl, alkenyl oralkynl group of 1-6 carbons.
 8. A compound of the general formula below,said compound being a cell-mitosis-inhibiting compound:

wherein: I. R_(a)-R_(k) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(h), R_(i), R_(k) independently is —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and R_(e) is —R₁, —OR₁, —OCOR₁,—SR₁, —F, —NHR₂, —Br, —I; or —C═CH; or B) each R_(a), R_(b), R_(c),R_(d), R_(k), is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; andeach R_(g), R_(h), R_(i), independently is ═O, —R₁, —OR₁, —OCOR₁,—SR₁—F, —Br, or —I; and R_(e) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —Br,—I or —C═CH; and I. Z′ is defined as follows: A) Z′ is X, where X is>COR₁,

 or B) Z′ is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I, and X′ is X, asdefined above; or X′ is also >C═O; and II. Z″ is defined as follows: A)Z″ is Y, where Y is —O—,

 where n is 0-6; or B) Z″ is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and R₂ independently is —H. orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 9. A compound of the general formula below, said compound beinga cell-mitosis-inhibiting compound:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(i), R_(j), R_(k);, R_(l), R_(m), R_(o)independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; andR_(g) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or —C═CH; or B)each R_(a), R_(b), R_(c), R_(t), R_(k), R_(l), independently is —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; and each R_(d), R_(e), R_(i),R_(j), R_(m), R_(o) independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F,—NHR₂, —Br, —I; and R_(g) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂,—Br, —I or —C═CH; and II. Z is defined as follows: A) Z is Y, where Y is—O—,

 where n is 0-6; or B) Z is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and R₂ independently is —H, orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 10. A compound of the general formula below, said compoundbeing a cell-mitosis-inhibiting compound:

wherein: I. R_(a)-R_(k) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(g), R_(h), R_(i), R_(k) independently is —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₁, —Br, or —I; and R_(e) is —R₁, —OR₁, —OCOR₁,—SR₁, —F, —NHR₁, —Br, —I or —C═CH; or B) each R_(a), R_(b), R_(c),R_(d), independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, or —I;and each R_(g), R_(h), R_(l), R_(k) independently is ═O, —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R_(e) is —R₁, —OR₁, —OCOR₁,—SR₁, —F, —NHR₁, —Br, —I or —C═CH; II. Z is defined as follows: 1) Z isY, where Y is —O—,

 where n is 0-6; or Z is

 where R_(n) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; where, in eachformula set forth above, each R₁ and R₂ independently is —H, orsubstituted or unsubstituted alkyl, alkenyl or alkynl group of 1-6carbons.
 11. A compound of the general formula below, said compoundbeing a cell-mitosis-inhibiting compound:

wherein: I. R_(a)—R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(d), R_(e), R_(f), R_(g), R_(h), R_(j), R_(k), R_(l), R_(m),R_(n), R_(o) independently is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br,or —I; and R_(i) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or—C═CH; or B) each R_(a), R_(d), R_(f), R_(j), R_(m), R_(n), R_(o)independently is —R₁, —OR₁, —OCR₁, —SR₁, —F, —NHR₂, —Br, —I; and eachR_(b), R_(c), R_(e), R_(g), R_(h), R_(k), R_(l) independently is ═O,—R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₃, —Br or —I; and R₁ is ═O, —R₁, —OR₁,—OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or —C═CH; or C) each R_(a), R_(b),R_(c), R_(d), R_(n), R_(o) independently is —R₁, —OR₁, OCR₁, —SR₁, —F,—NHR₂, —Br, —I; and each R_(e), R_(g), R_(h), R_(k), R_(l) independentlyis ═o, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R₁ is ═o, —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, —I or —C═CH; and I. Z is defined asfollows: 1) Z is X, where X is >COR₁,

 or Z is

 where R_(p) is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I; and X′ is X, asdefined above; or X′ is >C═O; where, in each formula set forth above,each R₁ and R₂ independently is —H, or substituted or unsubstitutedalkyl, alkenyl or alkynl group of 1-6 carbons; and the bond indicated byC...C is absent or, in combination with the C—C bond is the unit HC═CH.12. A compound of the general formula below, said compound being acell-mitosis-inhibiting compound:

wherein: I. R_(a)-R_(o) are defined as follows: A) each R_(a), R_(b),R_(c), R_(e), R_(g), R_(h), R_(k), R_(l), R_(m), R_(n), R_(o)independently is —R₁, —OR₁, OCOR₁, —SR₁, —F, —NHR₂, —Br, or —I; andR_(i) is —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I or —C≡CH; or B)each R_(a), R_(e), R_(l), R_(m), R_(n), R_(o) independently is —R₁,—OR₁, —OCOR₁, —SR₁, —F, —NHR₂, —Br, —I; and each R_(b), R_(c), R_(g),R_(h) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; and R_(i) is═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, —I or —C═CH; or C) eachR_(a), R_(b), R_(c), R_(e), R_(k), R_(n), R_(a) independently is —R₁,—OR₁, OCOR₁, —SR₁, —F, NHR₂, —Br, —I; and each R_(g), R_(h)independently is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br or —I; andR_(i) is ═O, —R₁, —OR₁, —OCOR₁, —SR₁, —F, —NHR₁, —Br, —I or —C═CH; andII. Z is defined as follows: A) Z is X, where X is >COR₁,

B) Z is

 where R is —R₁, —OR₁, —SR₁, —F, —NHR₂, —Br or —I, and X′ is X, asdefined above; or X′ is ═O; where, in each formula set forth above, eachR₁ and R₂ independently is —H, or substituted or unsubstituted alkyl,alkenyl or alkynl group of 1-6 carbons; and the bond indicated by C...Cis absent or, in combination with the C—C bond is the unit HC═CH. 13.The method of claim 1, wherein said cell-mitosis-inhibiting compositionis 2-methoxyestradiol.
 14. The method of claim 1, wherein saidcell-mitosis-inhibiting composition is 2-fluoroestradiol.
 15. The methodof claim 1, wherein said cell-mitosis-inhibiting composition is2-bromoestradiol.
 16. The method of claim 1, wherein saidcell-mitosis-inhibiting composition is 2-methoxyestrone.
 17. The methodof claim 1, wherein said cell-mitosis-inhibiting composition is17-ethynylestradiol.
 18. The method of claims 1 or 2 wherein saidcompound is further characterized in that A) Z′ is

 Z″ is

B) Z′ is X; and Z′ is

 or C) Z′ is

and Z″ is Y.
 19. The method of claims 3 or 4 wherein said compound isfurther characterized in that Z is


20. The method of claims 5 or 6 wherein said compound is furthercharacterized in that Z is


21. The compound of claims 7 or 8, wherein said compound is furthercharacterized in that A) Z′ is

 and Z″ is

B) Z′ is X; and Z″ is

C) Z′ is

and Z″ is Y.
 22. The compound of claims 9 or 10, wherein said compoundis further characterized in that Z is


23. The compound of claims 11 or 12, wherein said compound is furthercharacterized in that Z is


24. The method of any one of claims 1-6, wherein at least one ofR_(a)→R_(p) is —OCH₃.
 25. The compound of any one of claims 7-12,wherein at least one of R_(a)→R_(p) is —OCH₃.